采用有限元方法(finite element method, FEM) 计算了固体火箭发动机(solid rocket motor, SRM) 工作过程中及工作结束后的整体毡C/C 复合材料喉衬的温度场及应力场, 并将其应力极值与材料性能测试所得的强度极限值进行了比较分析. 结果表明, 在发动机工作过程中喉衬结构完整, 发动机工作结束后喉衬所承受的最大轴向拉应力超出了材料的轴向拉伸强度极限, 喉衬轴向受拉失效而纵向开裂. 最后, 通过发动机点火实验过程中及实验后喉衬的扫描电子显微镜(scanning electron microscope, SEM) 分析对实验分析结果进行了验证.
The temperature and stress fields of solid rocket motor (SRM) throat made of needled integral felt C/C composites during and after firing process are calculated using finite element method (FEM) in this paper. The calculated maximum stress in nozzle throat is compared with the final strength obtained in the material test. It has been found that the nozzle throat with needled integral felt C/C composites is safe during SRM firing, but the final axial tensile stress of nozzle throat after SRM firing exceeds the material tensile strength, leading to structure failure. The results are verified by SRM firing test and scanning electron microscope (SEM) analysis.
[1] 宋桂明, 周玉, 王玉金, 等. 固体火箭发动机喉衬材料[J]. 固体火箭技术, 1998, 21(2): 51-55; 61.
[2] 刘建军, 李铁虎, 郝志彪. 喉衬热环境与碳-碳复合材料的烧蚀[J]. 宇航材料工艺, 2005(1): 42-48.
[3] 郑权. 碳/碳复合材料喉衬热结构分析及失效行为研究[D]. 哈尔滨: 哈尔滨工业大学, 2011: 2-4.
[4] 苏君明. 整体毡C/C 喉衬的研制与应用[J]. 新型碳材料, 1997, 12(4): 46-49.
[5] 田四朋, 唐国金, 李道奎, 等. 固体火箭发动机喷管结构完整性分析[J]. 固体火箭技术, 2005, 28(3): 180-183.
[6] 陈汝训, 刘铭初, 李志明, 等. 固体火箭发动机设计与研究[M]. 北京: 中国宇航出版社, 1992: 117-228.
[7] 胡江华, 孟松鹤, 常新龙, 等. 锥形套式连接C/C 喷管扩张段温度场与应力场分析[J]. 固体火箭技术, 2012, 35(1): 64-68.
[8] Sun J F, Sun B, Xiang S H. Theoretical calculation of complex nozzle’s temperature profile and stress profile in solid rocket motor [J]. Journal of Propulsion Technology, 1994(2): 23-31.
[9] 黄宏艳, 王强. 轴对称喷管内外流场与结构温度场耦合计算[J]. 推进技术, 2008, 29(2): 194-198; 229.
[10] Sun B, Sun J F. A calculation about a temperature filed of boundary movement nozzle with finite element method [J]. Journal of Propulsion Technology, 1995, 16(5): 54-58.
